Babk-mill



W. TANSLEY.

Bark M'ill.

Patented May 29, 1860.

UNITED STATES PATENT OFFICE.

WILLIAM TANSLEY, OF SALISBURY CENTER, NEW YORK.

BARK-MILL.

Specification of Letters Patent No. 28,518, dated May 29, 1860.

To all whom it may concern:

Be it known that I, TVILLIAM TANSLEY, of Salisbury Center, in the countyof Her-kimer and State of New York, have invented a new and ImprovedMachine for Breaking and Grinding Bark Designed Chiefly for TanningPurposes; and I do hereby declare that the following is a full, clear,and exact description of the same, reference being had to the annexeddrawings, making a part of this specification, in which Figure 1, is avertical central section of my invention taken in the line 00, m, Fig.2. Fig. 2 a plan or top view of the same.

Similar letters of reference indicate corre sponding parts in the twofigures.

The object of this invention is to obtain a grinding mill by which dampor wet bark may be ground with facility and in a perfect manner. Thereare many forms of bark mills which will grind expeditiously and well drybark, but which will when fed with wet or damp bark become choked andclogged causing much trouble and delay besides working veryinefiiciently.

I propose to obviate this difliculty by employing rotary burs andstationary graters arranged in a novel way and also in using inconnection therewith breakers arranged to operate conjointly with theburs and graters to'effect the desired result.

To enable those skilled in the art to fully understand and construct myinvention I will proceed to describe it.

A, represents a conical cast-metal case of suitable dimensions havingarms a, a, within it and crossing each other at right angles, similararms 6, 6, being attached to the bottom of the case A.

B is a vertical shaft which is placed centrally in the case and has itsbearings at the points of intersections of the arms a, a, Z), Z), asshown clearly in Fig. 1.

To the upper end of the shaft B, there are two breakers c, 0, attached.These breakers are simply two arms of slightly curved form provided attheir outer end with a pendent toot-h (Z, as shown clearly in Fig. 1.

On the shaft B, below the arms a, a, there is placed a conical head C,and the upper end of this head has four radial arms 0, attached to theouter ends of which is secured a rim D. This rim D, transversely is ofinverted V form, as shown clearly in Fig. 1, and it is provided at eachside with teeth or burs d, every alternate one 1 of which extends fromthe bottom to the top of the rim, and the intermediate ones 2, extendingupward to a point about half the height of the rim as shown in bothfigures.

The base of the rim D, is a perfect circle, both of its sides, however,vary from this form. It may be described as having its sides formed ofeccentric sections which gradually increase in width from one end to theother, the thick or broad end of one section adjoining the thin end ofthe one next to it as clearly shown at a in Fig. 2. The rim D, isrepresented in Fig. 2, as being divided into four eccentric sections butmore or less may be used as described.

The conical head C, has a circular base, but its sides are also dividedinto eccentric sections similar to the rim D, and are provided withinclined teeth or burs 6, arranged precisely the same as the teeth orburs on the rim D, viz., every alternate tooth 3 extending the wholeheight of the cone and the intermediate ones 1, about one half of itsheight see Fig. 1.

The upper sides of the arms 0 are provided with teeth 7, of pyramidalform, and the under sides of the arms a, are provided with similar teeth9, the latter being in line with the spaces between the former as shownclearly in Fig. 1.

To the upper surfaces of the arms Z), 6,

there is attached an annular grater E, the

base of which is a perfect circle but the sides are composed ofalternate concave and convex sections b", c, as shown clearly in Fig. 2.The grater E, it will be seen by referring to Fig. 2, occupies aposition between the conical head C, and the rim D. The grater isprovided with teeth at its sides all of which extend its whole height.

At the lower part of the case A, at its inner side there is a toothedrim F. This rim is also composed of eccentric toothed sections preciselysimilar to the conical head C, and the rim D, the lower edge of the rimF, forming a perfect circle.

The conical head C, and rims D, and F, have their eccentric sections soformed, that they gradually lose their eccentricity, or graduallyapproach to a circle from their upper to their lower edges, the greatesteccentricity being at the top. The same also may be said respecting thesections of the grater E.

To the inner side of the case A, there are four projections Gr, placedat equal distances apart and cast with the case A. The

rim F, is also cast with-the-case A; All

the parts of the mill with the exception'of" the'shaft B, may be ofcasts-iron. i The operation is as follows: The shaft is rotated by anyconvenient power and the bark is put into the case A, the breakers'c, asthey rotate, reducing it to a certain extent so that it may pass down inthe case and be still further a'ctedflu'pon by the teeth f, g, of thearms a, a, the latter rotating with the shaft B, The bark is thenreduced sufficiently fine to passdown between the conical head G, andgrater E, and between the grater and rim D, and between the rims'D,

andFQthe bark bein discharged from between them in a sufficiently groundstate. The forming of the grinding parts above named of eccentricsections as herein described, prevents the bark from packing between thegrinding surfaces. This eifect is due to an irregular action of thegrinding surfaces on the bark produced by their ec-' leaving the upperparts of the spaces between' the grindingv parts more open" than theyotherwise would be and at the same time permitting ofa' proper grindingsurface at their lower parts.

This invention has been practically tested and it operates well,grinding wet bark in a rapid and perfect manner;

Having thus described my invention what I claim as new, and desire to;secure, by Let-i ters Patent, is e c J l; The formingof the conicalheadC, and

rims D, 'F, of abark mill of-eccentric sec-' tionssubstantially as andfor the'purpose set forth. c c f 2. The'grater E, whenformed of a seriesof alternate concave and convex I)", a, asvdescribed.

3. The crushing teeth 7, 9', formed respectively on the arms a, 0, whenused in connection with the head C,'rims D, F, and grater E, and placedin the relation thereto as and for the purpose set forth.

4; The alternate long and'short teeth or burs 1, 2, and 3,4,respectively on the rim D, and conical head C, as and for the purposespecified.

5. The combination of the head C, rims D,'F, and grater E, arrangedwithin a case A, for joint operation substantially as and for thepurpose set forth.

WILLIAM TANs L-EY.

Vvitnesses r A. GILBERTS,

G. W. BARNEsg sections it

